The inimitable Janet Reid shared this article on magic systems and world-building a few days ago:
My Magician Is Better Than Yours...
In the article, Jeff Somers covers magic systems - and how interesting or how boring they can be - as well as the trope of the Chosen One and how overdone it can be.
As examples, he offers four different stories with magic in them, none of which I have read. I'll have to check them out. One of them is actually rather similar to something that's been percolating at the back of my mind. It's true what they say: there are no new ideas!
The thesis of the article, though, is sound. Making your hero the hero because they have to be is much less interesting than them choosing to be.